Chapter 11

Question 1

Give a present day example of NATURAL SELECTION

Answer 1

The emergence of the super bug MRSA.

Antibiotics kill the susceptible bacteria and the resistant one alon. The survivors multiply producing a new generation of anti-biotic resistant bacteria.

Question 2

EVOLUTION

Answer 2

. Genetic change in a population over multiple generations

or

. Descent with modification

Question 3

Descent with modification

Answer 3

Descent refers to inheritance

modification refers to changes in the inheritable traits over generations

Question 4

POPULATION

Answer 4

interbreeding members of the same species living in the same place at the same time

Question 5

When does evolution happen in a population

Answer 5

when some alleles become more common and others less common from one generation to the next.

These changes in alleles account for both the long term and short term changes in the history of life on Earth

Question 6

What does evolution not answer

Answer 6

how did life begin in the first place

Question 7

SPECIAL CREATION

Answer 7

The idea that of the sudden appearance of organisms on Earth.

Species were fixed and unchangeable

Earth was relatively young

There could be no extinction

Question 8

The name of Darwins Ship

Answer 8

The HMS beagle

Question 9

CONVERGENT EVOLUTION

Answer 9

describes the acquisition of the same biological trait in unrelated lineages.

Question 10

NATURAL SELECTION

Answer 10

More individuals are produced than survive only those who are able to get the resources were more likely to survive and reproduce

. It occurs when encironmental factors cause the differential reproductive success of individual with a particular phenotype.

Question 11

ARTIFICIAL SELECTION

Answer 11

when a human chooses one or few desired traits and then allows only the individuals that best expresses those qualities to reproduce

Question 12

Explain theory of Darwin’s theory natural selection and evolution

His theory of evolution through natural selection

Answer 12

1. he observed that individuals in a species are different from one another
2. and some of these variations are inheritable
3. Competition determines which ones live long enough to reproduce: those with the most adaptive traits would more likely reproduce and pass on thos adptive traits to their offsprings.
4. Over many generations natural selectioncoupled with enviromental change or a new habitat could change a populations characteristics or give rise to a new species

Question 13

MODERN EVOLUTIONARY SYNTHESIS

Answer 13

It suggests that genetic mutations create inheritable variations and that this variation is the raw material upon which natural selection acts

. Mutations are changes in DNA sequence that occur at random in all organisms. Sexual reproduction amplifies the variability by shuffling and reshuffling parental alleles to produce genetically differnt offspringd

Question 14

The 2 types of biological evolution

Answer 14

1. MICRO EVOLUTION

2. MACROEVOLUTION

Question 15

Evolution and Alleles

Answer 15

Evolution involves changes in alleles. Because an individual ‘s allele does not change: evolution can occur in a population and not in an individual. Individuals do not Evolve they adapt

Question 16

MICROEVOLUTION

Answer 16

The relatively short term genetic changes in a population

most common example : Natural Selection

Question 17

MACROEVOLUTION

Answer 17

large scale events such as the appearance of a new species

Question 18

ADAPTATIONS

Answer 18

features that provide a selective advantage because they improve an organism’s ability to survive and reproduce.

They are inheritable traits that give an individual a competitive advantage

They include only those structures, behaviors or psychological processes that are inheritable and that contribute to reproductive success

In any population, individuals with the best adaptations are mostlikely to reproduce and pass their advantage to their offspring

Because of this “differential reproductive success” ( natural selection) a population changes over time and the best adaptations to the existing environmentbecome more common with each generation

Question 19

SELECTIVELY NEUTRAL

Answer 19

some features neither increase or decrease reproductive success ( surviving to be able to have offsprings that also survive)

eg certain phenotypes like the color of ones eye or mutations in silent dna that persist but are not subject to natural selection

Question 20

REPRODUCTIVE SUCCESS

Answer 20

surviving to be able to have offsprings that also survive)

Question 21

PHENOTYPE

Answer 21

Is the observable properties of an organism,most of which arise from a combination of environmentalinfluences and the action of multiple genes

Question 22

How does Natural Selection eliminate phenotypes

Answer 22

By weeding out individuals with poorly adapted phenotypes natural selection indirectly changes allele frequencies in the population

Question 23

What determines if a phenotype is good

Answer 23

it depends on the environment and time: a trait that is adaptive in one set of circumstances may be a liability in another

Question 24

Why does evolution never stop

Answer 24

Becauses conditions are always changing

Question 25

Evolution does not have a goal

What are the factors that combine to prevent natural selection from producing all the traits that a species might find useful

Answer 25

1. Every genome has limited potential imposed by evolutionary history
2. No population contains every allele needed to confront every possible change in the environment: If the right alleles are not available at the right time an environmental change may wipe out a species
3. Disasters such as floods can indiscrimantly eleminate the best alleles combination for that environment by chance
4. Genetic traits such as diseases that appear after repoductive age are not affected by natural selection

Question 26

FITNESS

Answer 26

1.is Reproductive Success. It is surving long enough to reproduce

Adaptations contribute to an organism’s fitness: allowing them to overcome environmetal changes,it also includes

2. attracting a mate

3. number of of offsprings a organism produces

4. the total number that survives to reproductive age

Question 27

What is evolution

Answer 27

Evolution is genetic change in a population over time

Question 28

How did people think that species arose and diversified before Charles Darwin published his theory of evolution by natural selection?

Answer 28

The major belief was in a special creation in which God formed all species and placed them on the earth. Jean Baptiste de Lamarck proposed that acquired characteristics were heritable; differential use and disuse of body parts accounted for changes between generations and species diversification.

Question 29

What did Darwin observe that led him to develop his ideas about the origin of species?

Answer 29

As Darwin journeyed in the HMS Beagle, he observed the uniformity of geological processes such as volcanism, earthquakes, and erosion. He collected fossils and observed that each continent had animals that were characteristic and different from those on other continents. On the Galapagos, he observed and collected finches from different islands and noted differences in giant tortoises on different Galapagos Islands. These observations led Darwin to the idea of “descent with modification

Question 30

How is artificial selection different from natural selection

Answer 30

In artificial selection, humans select for the traits they desire in plants or animals. In natural selection, environmental factors favor some traits over others.

Question 31

How did Darwin’s ideas challenge prevailing beliefs about life’s diversity and the status of humans?

Answer 31

Darwin’s ideas challenged prevailing beliefs about life’s diversity by using natural processes to explain how species arise. Darwin saw humans as just another species and rejected the idea that humans were specially created. He thereby demoted humans from an exalted position, putting them on an equal footing with other species competing for resources.

Question 32

What is the modern evolutionary synthesis?

Answer 32

The modern evolutionary synthesis combines the work of Darwin with a modern understanding of genes, chromosomes, and the origins of variation.

Question 33

What is an adaptation, and how do adaptations become more common within a population?

Answer 33

An adaptation is a characteristic that helps an individual survive and reproduce in its environment. Adaptations become more common within a population when they are heritable and when they increase the odds of survival and reproduction.

Question 34

What is the role of genetic variation in natural selection?

Answer 34

Genetic variation is the raw material that natural selection acts on since genetic variation creates variations in phenotypes, some of which are better suited to the current environment.

Question 35

How can natural selection favor different phenotypes at different times?

Answer 35

Natural selection can favor different phenotypes at different times because environments are always shifting in dramatic or subtle ways.

Question 36

Why doesn’t natural selection produce perfectly adapted organisms?

Answer 36

Natural selection does not produce perfectly adapted organisms because each population’s evolution is constrained by its existing gene pool, which limits the possible allele combinations and may not contain every allele necessary to confront every challenge. Chance events may also wipe out adaptive allele combinations. Genetic illnesses that produce symptoms only after reproductive age also can maintain harmful alleles in a population.

Question 37

What is evolutionary fitness?

Answer 37

Evolutionary fitness is measured by reproductive success